Synthesis and characterization of a new Schiff base derived from pyridoxal and 2,3-diaminopyridine and its Cu(II) and Ni(II) complexes

Authors

• Maryam Jabbari ¹
• Sadegh Allameh * ¹
• Hossein Behmadi ¹

• Department of Chemistry, Mashhad Branch, Islamic Azad University, Mashhad, Iran

Abstract

Schiff bases are multi-purpose ligands that are synthesized by condensing primary amines with carbonyl groups in aldehydes or ketones. In this work, my ligand, [2-methyl-4-((E)-((2-(((Z)-(3-hydroxy-5-(hydroxymethyl)-2-methylpyridine-4-yl)methylene)amino)pyridine-3-yl)imino)methyl)-5-(hydroxymethyl)pyridine-3-ol] (H2L) , was preparated from the reaction of 2,3-diaminopyridin and pyridoxal. Ni and Cu Complexes based on this ligand were also synthesized and the construction of the ligand and the complexes have been proved by experimental ways.

The construction parameters and spectral properties of ligands and their complexes were studied using density functional theory (DFT). In the tetrahedral geometry of the two complexes, the dianionic form of the Schiff base acts as a tetradentate ligand and is coordinated with Cu2+ and Ni2+ ions by two azomethine nitrogens and two phenolate oxygens. The good agreement between the experimental values the IR wave numbers and the NMR chemical shift with the values predicted by DFT shows the validity of the optimized geometries for the studied species.

Keywords

• DFT
• 2-3-Diaminopyridine
• Pyridoxal
• Schiff base
• Cu and Ni complex